1. Field of Invention
The field of this invention relates to hand tools for the purpose of turning rotary fasteners, and more specifically to wrenches that have two pivoting wrench heads mounted on a single pivotal hinge.
2. Background
The present state of the art for hand tools is very diverse. For wrenches, a typical set of hand wrenches can come in sets of six or more sizes and various styles. These sets usually come in a carrying case or other holding structure to keep the multiple tools together. The disclosed double nested wrench ends allow for four or more wrench sizes to be ergonomically positioned on one end of a handle or tool arm using a single pivotal hinge or pivot pin. This single pivotal hinge can comprise a pressure fitted pivot pin, a riveted pivot pin, threaded pivot pin, or other pivotal hinge mounting means. The disclosed double nested wrench designs can also be configured with a folding hinge to allow a short, low-profile position for stowage. This stowed position can be accomplished by including a folding hinge near the center of the hand tool so that each end of the hand tool can fold substantially together on one side of the folding hinge. In this way, a very compact stowed position can be achieved for folding hand tools with double nested wrench ends and additional tools (e.g., a screwdriver).
Wrench and socket heads have been used for nearly a century to turn a rotary fastener of various sizes and shapes. Sockets typically have a significant vertical height when engaging a rotary fastener. Sockets also tend to be designed to be removable from the tool handle or tool arm so that only one wrench handle or ratchet wrench is need for the entire set of sockets. Wrench heads on the other hand, generally have a much lower profile (smaller vertical height above a rotary fastener during use) than a socket, and/or are normally permanently attached to its tool arm (handle). The exact difference in structure between a “socket” and a “wrench head” is blurred by the fact that both provide similar functions, but the difference often comes down to the fact that most “sockets” are designed for removable attachment to a wrench handle, or ratchet and also tend to have a much higher vertical profile. For the disclosed double duplex wrench heads presented here, the vertical profile (vertical height) of the wrench head can have a wide variety of lengths depending on the intended use. For most wrench applications, the duplex wrench heads presented here can be permanently attached to its respective wrench head pivot arm. Depending on the intended use, the wrench head gripping surfaces can have a longitudinal length (vertical height) ranging from a fraction of its gripping surface's diameter to as great as three times its exterior diameter. Duplex wrench heads shorter than the diameter of its gripping surface (see duplex wrench head assemblies 71a and 72a in FIG. 4A) can be used to reach rotary fasteners in vertically tight spaces, while the longer duplex wrench heads (see duplex wrench head assemblies 71b and 72b in FIG. 4A) can be used to reach rotary fasteners within indented areas. Thus, the vertical height of a wrench head or a wrench socket can be thought of as the height the wrench head or socket extends above a surface when engaging a rotatory fastener on that surface and would include any additional height from the wrench handles, ratchets, and arms that are positioned above the rotary fastener when the wrench or socket is engaged for use.
In FIG. 1A, we see duplex wrench head 20 is shown with a longitudinal length slightly less than the diameter of its larger gripping surface 21. In FIGS. 1C-D, we see prior art Craftsman® Figure Eight® wrench comprising a duplex wrench heads 20a which has a tool length (vertical height during use) approximate equal to the diameter of its larger gripping surface 21a. In FIG. 4A, we see a wrench heads 71b and 72b with a vertical height that is approximately twice the diameter of its larger gripping surface 33b and 37b, respectively. In the disclosed invention, the longitudinal length, or vertical height, of the wrench heads can be increased to two, three, or four times its diameter to provide specific wrench needs. As the longitudinal length of the wrench heads increase above twice its gripping surface diameter, the wrench heads can reach down into deeper and deeper indentations to turn a rotary fastener and begin to provide a socket-like function for the hand tool.
The duplex wrench heads presented here can comprise a variety of gripping surfaces for use with different types of fasteners. Some of the rotary fastener gripping surfaces commonly used today comprise: 1) four-point standard (square shape), 2) six-point standard (hexagon shape, see FIG. 3A), 3) twelve-point standard (double hexagon, see FIG. 3B), 4) twelve-point spline (see FIG. 3B), 5) lobed gripping surfaces (both six and twelve point), 6) Torex® gripping surfaces, 7) asymmetric gripping surfaces, 8) variations on these basic gripping surfaces, and 9) many other specialty shape surfaces for various purposes. This list of gripping surfaces is not exhaustive and many other gripping surface designs exist in the patent record that can be used with the disclosed folding wrench system. Besides a large variety of gripping surface types, wrench heads also come in various configurations such as box-end wrench heads, open-end wrench heads, flare nut wrench heads, overlapped wrench heads, duplexed wrench heads, overlapped and duplexed wrench heads, ratcheting open-end wrench heads, Jonard Speed wrench heads, and many other specialty wrench heads.
3. Prior Art
In the prior art, duplex wrench heads have been used in various configurations. A few designs exist in the prior art that provide multiple duplex wrench heads in a single wrench end or pivotal duplexed wrench ends, however none were found that provide a double duplex wrench end that provides two pivotal duplex wrench heads with wrench head arms nested one inside to reduce the overall width and size of the wrench as disclosed by the Applicant.
Pivotal duplexed wrench heads are shown in U.S. Pat. No. 1,613,976 to Bellows, U.S. Pat. No. 5,325,744 to Horikawa, U.S. Pat. No. 6,112,625 to Turtle, and U.S. Pat. No. 8,230,766 to Chang. Two duplex wrench heads combined on one tool end are shown in U.S. Patent Application 2011/0120275 to Macor, U.S. Pat. No. 8,302,510 to Macor, and U.S. Pat. No. 8,230,766 to Chang. Four sided pivotal wrench heads are shown in U.S. Patent Application 2012/0060653 to HSU, U.S. Pat. No. 8,069,753 to Kriz, U.S. Pat. No. 7,966,912 to Hobden, U.S. Pat. No. 1,796,083 to Carlberg, U.S. Pat. No. 1,571,148 to Sisolak, and U.S. Design Pat. No. D658,459 to Meholovitch. Also, U.S. Pat. No. 6,109,142 to Learng shows a sliding duplex socket with four gripping surface sizes, and U.S. Pat. No. 1,930,238 to Heller shows a six sided wrench socket that removably attaches at different positions for use.